Valve actuating structure for inflatable assemblies



E. HARTMANN Feb. 26, 1963 VALVE ACTUATING STRUCTURE FOR INFLATABLE ASSEMBLIES Filed May 22, 1961 2 Sheets-Sheet l 13M mm m W T Q 0 w Fm. m 7/ m ms GI? .T M m In m m Feb. 26, 1963 E. HARTMANN 3,079,018

VALVE ACTUATING STRUCTURE FOR INFLATABLE ASSEMBLIES Filed May 22, 1961 2 Sheets-Sheet 2 2/ /7 20 KJOOOOOOO'OOOfii/OGOOOO OOOOOOGOOOOO OOOOOOUOOOO E OOOOOOOOOOOOOOOOO/ Y highmeL $.S'hlk2r ATTORNEY INVENTOR ljnite 3,G79,fll3 VALVE ACTUATENG STRUQTURE FGR lNFLATABLE ASSEMBLlEfl Ewald Hartmann, Koln-Nippes, Germany, assignor to Franz Clouth, Koln-Nippes, Germany Filed May 22, 1961, Ser. No. 111,800 7 Claims. (Cl. 2l4-l'7) The present invention relates to inflatable assemblies.

More particularly, the present invention relates to inflatable assemblies of the type which are used in storage bins and the like to break up agglomerations of particulate material in the storage bins so as to render the particulate material flowable.

Such inflatable assemblies conventionally include a chamber which is formed by a rigid wall and a stretchable wall which is, for example, coextensive with the rigid wall. When the stretchable wall becomes stretched to a predetermined extent a valve is opened so as to place the interior of the chamber in communication with the outer atmosphere and in this way the chamber becomes deflated.

Inflatable assemblies of this type have several defects. Thus, it often happens that the particulate material gives way quite suddenly so that there is a sharp increase in the differential of the pressure in the interior of the chamber with respect to the pressure of the particulate material which bears on the exterior of the stretchable wall, and as a result the stretchable wall suddenly becomes very sharply tensioned and there is a sudden impact which actuates the valve which opens the chamber to the outer atmosphere, and this often results in failure of some part of the inflatable assembly.

Moreover, with assemblies of this type when the chamher is deflated the stretchable wall bears directly against the rigid wall so that the stretchable wall does not have any cushioning influence with respect to the particulate material clumps of which strike against the inflatable assembly, and furthermore there is an undesirable frictional rubbing between the inner surface of the stretchable wall and the inner surface of the rigid wall.

One of the objects of the present invention is to provide an inflatable assembly of the above type which will reliably prevent a sudden impact-type of operation of a release valve so as to protect the latter as well as remaining parts of the inflatable assembly in the event that there is a sudden reduction in the pressure of the particulate material on the exterior of the stretchable wall of the inflatable stretchable wall of the inflatable assembly.

Moreover, it is an object of the present invention to provide for an inflatable assembly of the above type a structure which will reliably maintain the inner surface of the stretchable wall spaced from the inner surface of the rigid wall of the chamber of the inflatable assembly. In this way there will be maintained between these walls a layer of air which will act as a cushion to damp the impact of clumps of particulate material which happen to strike against the inflatable assembly in the interior of the storage bin or the like, and moreover with this construction the frictional rubbing of the inner surface of the stretchable wall against the inner surface of the rigid wall is very greatly reduced.

it is furthermore an object of the present invention to provide a structure of the above type which will accomplish the above objects and which at the same time is composed of simple rugged elements which are very reliable in operation.

With the above objects in view the invention includes, in an inflatable assembly which is adapted to be used with storage bins or the like, a chamber made up of a pair of wmls one of which is rigid and the other of which is flexible, these walls being substantially coextensive and 3,fl?9, l 8 Eatented Feb. 26, 1963 joined fluid-tightly to each other at their peripheries. The rigid wall carries a valve means which in its open position places the interior of the chamber formed by said walls in communication with the outer atmosphere and which in a closed position closes off the interior of the chamber means from the outer atmosphere. A valve-operating means is connected to the stretchable wall and to the valve means to automatically open the latter when the stretchable wall has been stretched beyond a predetermined extent, and in accordance with the present invention this valve-operating means includes a plurality of endless stretchable bands operatively connected at one end to the valve means and at the opposite end to the stretchable wall. The stretchable wall has at its interior a plurality of projections to which the outer ends of the endless stretchable bands are connected, and these projections maintain the inner surface of the structural wall spaced from the rigid wall even when the chamber is deflated so as to greatly reduce the friction between these walls and so as to maintain between the walls a layer of air which acts as a cushion to damp the impact of clumps of particulate material which fall against the inflatable assembly in the interior of the storge bin or the like.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

FIG. 1 is a diagrammatic sectional fragmentary elevation of a storage bin showing diagrammatically inflatable assemblies according to the invention mounted within the storage bin;

FIG. 2 is a sectional view on an enlarged scale taken along line 2-2 in the direction of the arrows of FIG. 1 and showing in section an inflatable assembly according to the present invention;

PEG. 3 is a top plan view of an inflatable assembly according to the present invention, part of the stretchable wall of the inflatable assembly being broken away so as to more clearly illustrate the structure within the inflatable assembly of the invention;

FIG. 4 shows, on an enlarged scale as compared to FIG. 2, a valve structure of the inflatable assembly of the invention;

PEG. 5 is a fragmentary illustration on an enlarged sale, as compared to FIG. 2, of a means which cooperates with an opening of the stretchable wall to maintain this opening closed until the stretchable wall has been stretched beyond a predetermined extent; and

PEG. 6 shows in a top plan view part of a structure of the invention which limits the flow of fluid to a direction from a diaphragm of the inflatable assembly to the outer atmosphere.

Referring now to H6. 1 of the drawings, there is shown diagrammatically therein a storage bin ill which is adapted to contain any particulate material 11. This particulate material which may take the form of any grain or the like may, due to dampness, for example, become agglomerated, and as a result the particulate material 11 will not readily flow out of the container 18. In order to prevent this undesirable result from taking place, there are provided within the storage bin or container 10' a plurality of inflatable assemblies 12 according to the present invention. Fluid under pressure derived from a suitable compressor (not shown) is delivered to the inflatable assemblies 12 so that these assemblies bulge outwardly and as a result expand into the particulate material 11 to break up agglomerations thereof and thus promote downward flowing of the particulate material out of the container 16 in the direction of the arrow 13 shown in FIG. 1.

The details of each inflatable assembly 12 according to the present invention are shown in the remaining drawings. Referring toFIG. 2, it will be seen that the inflatable assembly 12 is mounted on the wall 14 of the storage bin, container, or the like, and this wall is formed with an opening 15 for a purpose described below. The inflatable assembly 12 includes a rigid Wall 16 and a stretchable wall 17 which in its unstretched condition is substantially coextensive with the rigid wall 16. The wall 16 may be made of a suitable metal, while the wall 17 may be made of rubber or any other desired elastomeric material.

The rigid Wall orplate 16 is fluid-tightly joined to an endless member 18 which serves to maintain the wall 16 spaced from the inner surface of the wall 14, and the space 19 between the wall 16 and the wall 14 is surrounded by the endless member 18-and maintained fluidtightly separate from the interior of the container or storage bin 10. The endless member 13 may be made of rubber or the like, and it is fluid-tightly joined to the Wall 16 at the periphery thereof as by being glued thereto, for example. Before such gluing or the like bolts 20 extend through openings of the wall 16 into recesses provided in the endless member 18 and suitable nuts and washers are located in these recesses and threadedly joined to the bolts 20, as is apparent from FIG. 2. The periphery of the stretchable wall 17 is located against the periphery of the wall 16 at the side of the latter opposed from the endless member 18, and a ring 21 extends all around the periphery of the stretchable wall 17, this ring or endless element 21 being formed with openings which are aligned both with the openings of the stretchable wall 17 and with the openings of the wall l'through which the bolts 20 respectively extend, so that in this way the bolts 20 extend through all of the series of aligned openings. A plurality oi-fastening studs 22 are embedded in the wall 14, as indicated in FIG. 2, and L-shaped straps 23 are respectively formed with openings through which the studs 22 pass as indicated in FIG. 2, so that these straps 23 may be used to rigidly fix the inflatable assembly to the wall 14. For this purpose the straps 23 are respectively formed at their ends which overlie the endless ring 21 with openings through which bolts 20 also pass, as indicated in FIG. 2, and in this way the straps 23 are fixed to the inflatable assembly of the invention. The nuts which are threadedly carried by the studs 22 are pressed tightly against the straps 23 so that in this way the entire assembly is fixed to the wall 14, and the several bolts20 are of course tightened so that the periphery of the stretchable wall 17 is fluid-tightly joined to the periphery of the wall 16, the endlessmember 21 pressing against the entire periphery of the stretchable wall 17 to maintain it in fluid-tight engagementwith the periphery of the rigid wall 16. The openings of the endless member 18 which receive the nuts which are threadedly connected to the bolts 20 are of a non-circular configuration and do not provide any substantial clearance for the nuts so that they cannot turn in these openings and thus the turning of the bolts 20 will serve to tighten the ring 21 against the periphery of wall 17 so as to press the peripheries of the walls 16 and 17 tightly against each other to guarantee fluid-tightness.

A tubular fitting 24 passes through an opening of the wall 16 and is welded to the latter, and the interior of the fitting 24 is threaded so as to have threadedly connected thereto the elongated tube 25 which passes fluid-tightly through the wall 14 of the storage bin and which at the exterior of the latter is connected in a well-known way .with a source of fluid under pressure so that in this way fluid under pressure is delivered through the tube 25 and the fitting 24 to the interior of the chamber 26 which is formed between the walls 16 and 17. This fluid under pressure may simply be air which is derived from a tank to which air under pressure is delivered from a conven- .tional air compressor, and the tube 25 itself or a flexible conduit which is in communication with the tube 25 is provided with a manually operable valve which is used for placing the air compressor or its tank in communication with the tube 25 and the interior of the chamber 26 and for cutting oil the supply of fluid under pressure, as required.

The wall 16 is formed at a substantially central portion with an opening 27 through which the fluid under pressure is adapted to flow to the outer atmosphere, when the opening 27 is opened in the manner described below, the fluid under pressure flowing through the opening 27 to the passage 15 and from the latter to the outer atmosphere. A valve means is provided for opening and closing the opening 27, and this valve means includes a flexible diaplnagm 23 made of any suitable material which is impervious to air and which is flexible so as to be movable to and from a position pressing against the edge of the opening 27 of the plate 16. The diaphragm 28 is of a generally circular configuration and is located at the exterior of the chamber 26 extending across the opening 27. The diaphragm 28 is shown in transverse section in FIGS. 2 and 4, and as is apparent from FIGS. 2 and 4 the diaphragm 28 has a central portion extending into the opening 27, an intermediate annular portion spaced from the wall 16, and an outer peripheral portion 29 which extends back toward and engages at its free edge the wall 16 at the outer surface of the latter. A rigid tube 30 passes fluid-tightly through the diaphragm28 and is joined to the latter as by being glued thereto, for example, although the tube 39 may be vulcanized to the diaphragm 28, if desired, and the tube 30 passes through a dished wall 31 to which the tube 30 is also fluid-tightly joined.

The dished wall 31 hasits concave surface directed toward the central portion of the diaphragm 28 and defines with the central portion of the diaphragm 28 aswell as with the tube 30 an annular enclosure 32. The inner end of the tube 31} is open so that when fluid under pressure is delivered to the interior of the chamber 2t; this fluid under pressure may flow into the tube 30. The tube 36 is formed with a plurality of bores 33 which provide communication betweenthe interior of the tube 30 and the enclosure 32, andin this way the fluid under pressure flows from the interior of'the tube 3.1? through the bores 33 into the enclosure 32. As is apparent from FIGS. 2 and 4, the area of the diaphragm 28 which is directed toward the interior of the chamber 26 and surrounded by the edge of the opening 27 is smaller than the area of the diaphragm 28 which is located at the enclosure 32, so that as a result the fluid under pressure in the enclosure 32 acts to move the diaphragm 28 toward the interior of the chamber 26 to close the opening 27 and in this way the chamber 26 is closed and the fluid under pressure delivered to the interior of the chamber 2% will continue to stretch the wall 17 so as to increase the interior volume-of the chamber 26 when fluid under pressure flows through the tube 25 and the fitting 24 through the interior of the chamber 25.

A plurality of bolts 34 pass through openings of the wall 16 and through aligned spacers 35 and then through aligned openings of the additional wall 31 and diaphragm 28, and these bolts 34 carry nuts 35 which thus serve to fix the periphery of the wall 31 fluid-tightly to the diaphragm 28 at the annular intermediate portion thereof and also the bolts 34 together with the nuts 35 serve to mount the entire valve assembly on the wall 16 in the manner illustrated in FIGS. 2 and 4.

A valve means is located within the tube 30 for the purpose of maintaining the enclosure 32 out of communication with the outer atmosphere so that the fluid under pressure in the enclosure 32 will maintain the diaphragm 28 against the edge of the opening 27 so as to maintain the chamber 26 closed. This latter valve means includes a ball valve member 36 which is fixed, as by welding, for example, to a member 37 which is axially movable within the tube 30 and which has a substantial clearance therein so that fluid can clearly flow past the member 37 within the tube 3%. An annular member 38 is threaded to the interior of the tube 3% at its inner end which is directed toward the chamber 26, and the annular member 33 is engaged by one end of a coil spring 39 whose opposite end presses against the member 37. The valve means further includes a plate 50 which is fixed to and extends across the interior of th tube 39, and this plate at is formed with a central opening 41. As long as the ball member 325 is pressed against the opening 41 to close the latter fluid cannot escape from the enclosure 32 to the outer atmosphere and the diaphragm 23 closes the opening 27 of the wall 16. Thus, the spring 39 as well as the fluid under pressure within the chamber 26 urges the valve 36 to its closed position closing the opening 41 and thus maintaining the diaphragm 28 in its closed position, and the parts thus cooperate to receive the fluid under pressure in the chamber 28 and continue to stretch the stretchable wall 17.

A valve-operating means which is described below coperates with the member 3 7 to displace the latter longitudinally along the tube 3% in opposition to the spring 39 when the wall 17 has been stretched beyond a given extent, and when this valve-operating means thus moves the member 37 the ball member 36 will of course move with the member 37 away from the opening 41 so that the fluid within the enclosure 32 can now flow to the outer atmosphere through the opening 51. As a result the fluid under pressure within the chamber 26 is now capable of displacing the diaphragm 23 away from the edge of the opening 27 and the fluid under pressure can now freely flow to the outer peripheral portion 2? of the diaphragm 28 and can move the outer peripheral portion 29 away from the wall 16 so that the fluid under pressure can freely escape to the outer atmosphere, this fluid under pressure flowing after moving past the outer portion 29 of the diaphragm 24% through the passage 35 of the wall 14 to the outer atmosphere. The presence of the outer peripheral portion 2W or" the diaphragm 28 keeps foreign matter from having access to the valve structure as well as to the diaphragm 2S and the interior of the chamber 26 when the latter is deflated, the portion 29 of the diaphragm 28 resiliently pressing against the wall 16 as a result of the inherent resiliency of the material of the diaphragm 23.

The valve-operating means includes a plurality of stretchable endless bands 42 made of rubber, for example. These bands are uniformly distributed about the axis of the opening 2'7 and are symmetrically arranged with r spect to the wall 17, as is apparent from FIG. 3. A red 43 is fixed to the member 37 and extends therefrom freely through the member t3 to where the rod 43 is fixed to a plurality of rods 44 (FIG. 3), and these rods 44 extend along diagonals of a rectangular frame 4 the arms of which respec 'vely turnably support rollers as by extending through axial bores of these rollers 45. Thus, in the illustrated example there are four endless stretchable bands 42 and four freely turnable rollers 4s connected by way of the rectangular frame 45 and the rods 43 and 44 to the member 37 which fixedly carries the ball valve member so.

A plurality of additional rollers 47 are turnably supported by the wall 17 at its interior, and the bands 4-2 respectively pass around the rollers 47 as well as the rollers as, as is apparent from FIGS. 2 and 3. The wall 17 is provided at its interior with a plurality of projections 48 which are integral with the Wall 17, and substantially U-shaped clamp members 49 extend around the projections 48 in annular grooves thereof, respectively, for example, and these clamps 49 are fixed to the ends of short rods which extend respectively through axial bores of the rollers 47, so that in this way the rollers 47 are clamped to the projections 48 of the Wall 17'.

The above-described structure will have several advantages in its operation. Thus, when the wall 17 has stretched beyond a predetermined extent the tension of the bands 42 will be suflicient to raise the element 37 in opposition to the spring 39 and automatically open the chamber 26 in the manner described above, so that in this way there is a limit to the expansion of the chamber 26. Of course, when the wall 17 contracts sufliciently, assuming that there is a continuous supply of fluid under pressure to the interior of the chamber 26 through the tube 25, the spring 39 as well as the pressure within the chamber 26 will again close the valve means within the interior of the tube 30, and thus the fluid under pressure will again move the diaphragm 28 to its position closing the opening 27, and the wall 17 will then stretch again while the volume of the chamber 26 again increases. It sometimes happens that the par ticulate material which is acted upon by the wall 17 gives way quite suddenly so that there is a sudden release of the pressure of the particulate material on the exterior of the wall 17, and as a result the wall 17 suddenly stretches to a considerable extent. In such a case if the valve-operating means includes non-stretchable elements there will be a sudden movement of the element 37 toward the element 38 and the impact of the structure will cause a considerable reduction in the lite thereof and perhaps failure of the valve structure. The use of the stretchable endless bands 42 prevents such an undesirable result from occurring since such sudden increase in the stretching of the wall 17 will be taken up to a considerable extent by stretching of the bands 42 which thus protect the valve structure. Moreover, when the chamber 26 is deflated the projections 58, which serve as a.- highly eflicient means for connecting the rollers 47 to the wall 17, will act as spacers to maintain the wall 17 spaced from the wall 16 in the deflated condition of the inflatable assembly of the invention, and as a result they will maintain between the walls 16 and 17 a layer of air which will act as a cushion to damp the blow of any clumps of particulate material which happen to strike against the wall 17 in the interior of the storage bin or the like. In addition, these projections 48 will serve to greatly minimize frictional rubbing of the inner surface of the wall 17 against the inner surface of the wall 16, because of the maintenance of the layer of air between the walls 16 and 17, and in this way the life of the wall 17 is also very greatly increased.

As is apparent particularly from FIG. 3, the inflatable assembly is of a substantially rectangular configuration, although it may have any desired polygonal or even circular configuration, if desired, and at the periphery of the inflatable assembly, more particularly at the corners thereof the wall 17 is formed with openings 5d, respectively. A means is carried by the wall 17 at each of its openings 56 for maintaining these openings 56 closed until the Wall 17 has been stretched beyond a given extent. This means 51 is shown most clearly in FIG. 5. The means 51 for closing each of the openings Sill includes an elongated resilient substantially mushroomshaped member 52 which has a shank portion passing through the opening 50. The wall 17 is formed with a recess 53 which receives the enlarged head 54 of the member 52, and this head 54 is formed with spaced projections 55 distributed around the head 54- and engaging the exterior surface of the wall 17 so as to provide spaces between the projections 55. The element 52 has a substantially pointed free end portion ss which is first introduced through the opening 5i when the element 52 is pulled through this opening St} to the position shown in FIG. 5, and a resilient lip 57 is also pulled through the opening 50, this lip 57 extending around the shank of the element 52 and being directed toward the wall 17. Once the element 52 is pulled throughthe opening to the position shownin FIG. 5, an annular member 58 which is also of a resilient stretchable material is moved along the substantially pointed portion 56 toward the wall 57 and is snapped over the lip 57 to be located at the side thereof which is directed toward the wall 17, and this annular member 58 is also'provided with projections 59 which are substantially identical with the projections 55. The diameter of the opening 50 before the means 51 is mounted on the wall 17 is indicated in dotted lines in FIG. 5. Thus, when the element 52 is passed through the opening 56 the wall 17 presses resiliently against the element 52 in the rest position of the wall 17. However, as the wall 17 stretches the diameter of the opening 50 will increase, and when the diameter of the opening 50 has increased sufficiently to render the opening 59 of a diameter larger than the shank of the element 52, as indicated, for example, in dot-dash lines in FIG. 5 and as is shown at the left portion of FIG. 2, the fluid under pressure within the chamber 26 can freely flow through the spaces between the projections 59 and through the opening 56 to the spaces between the projections 55 and, so into the interior of the storage bin or the like, so that the fluid under pressure itself may contribute to the breaking up of agglomerations.

The location of the openings 50 at the corners of the wall 17 and the mounting of theseveral means 51 respectively in the openings 56 to maintain these openings closed until the wall" has been stretched beyond a predetermined extent provides a considerable advantage. Thus, it may happen that the particulate material presses against the central portion of the wall 17 with such a pressure that when fluid under pressure is introduced into the chamber 26 the wall 17 cannot immediately move away from the central portion of the wall 16 and instead fluid under pressure flows only to a localized portion at one of the corners of the, inflatable assembly to expand and stretch the wall 17 only at one corner, for example. Under normal conditions where the wall 17 would be operatively connected only with the valve means carried by the central portion of the wall 16, the localized stretching of the wall 17 would result in bursting of the wall 17 at the area where the stretching occurs. However, with the openings 50 and the several means 51 the stretching even at localized portions will take place only until the opening 50 of the stretched portion becomes open and the fluid can then escape so that 'in'this way bursting of the wall 17 at localized portions thereof is reliably prevented. Furthermore, if the agglomerated condition of the particulate material is such that the fluid cannot escape even after the wall 17 stretches sufficiently to cause the openings 50 to become open, it will be noted that the valve-operating means 42 will still be operative to move the valve member 36 away from the opening 41 and release the fluid from the interior of the chamber 26, so that the valve structure formed by the means 51 together with the opening 50 and the valve structure carried by the central portion of the wall 16 complement each other and guarantee thatirrespective of the behavior of the material within the storage bin the inflatable assembly will operate properly.

As is apparent from FIGS. 2 and 3, a plurality of blocks 60 are fixed to the inner surface of .the wall 16 adjacent to the opening 27 thereof and are uniformly distributed about the opening 27. These blocks 63 may be made of any suitable material such as rubber, wood, or the like, and may be fastened in any desired way to the wall 16 as by being bolted thereto, glued thereto, etc. The purpose of these blocks 66 is to maintain the wall 17 spaced particularly at its central portion from the inner open end of the tube '30. It may happen that the particulate material presses on the stretchable wall 17 in such a way that it places the wall 17 against the inner end of the tube 30to close the inner end of the tube 30 with the result that when the fluid under pressure flows into the chamber 2-6 this fluid under pressure will not be able to flow into the tube 36 and through the bores 33 into the enclosure 32 for moving the diaphragm 28 to its closed position. The result is that the chamher 26 cannot become inflated since the fluid under pres sure simply flows into the chamber 26 and immediately out of the latter through the opening 27 and past the edge 29 of the diaphragm 23 in the manner described above. The presence of the blocks 611 guarantee that the central portion of the wall 17 will at all times be spaced from the inner open end of the tube 36 and is incapable of closing this part of the tube 39 so that closing of the opening 27 is guaranteed. It will be seen that because of the flexible resilient nature of the wall 17 the particulate material can press the wall 17 around the structure located at the inner open end of the tube 30 and the sleeve 38 in such a way as to prevent the fluid under pressure from reaching the sleeve 38 through which the rod 43 passes, and in such an event the diaphragm 28 would not be moved to its closed position. The blocks 60 guarantee, however, that the fluid under pressure will reliably flow to the side. of the diaphragm 28 which is directed toward the interior of the enclosure .32 so as to move the diaphragm 23 to its closed position in the manner described above.

When the wall 17 has stretched to an extent suflicient to cause the valve-operating means to automatically open the valve means in the tube 30, the enclosure 32 will be placed in communication with the outer atmosphere so that the fluid under pressure in the chamber 26 will automatically displace the diaphragm 28 away from the edge of the opening 27 and will flow to the outer atmosphere through the passage 15, as was pointed out above. However, as is particularly apparent from FIG. 2, the size of the passage 15 with respect to the volume of fluid under pressure which suddenly is released from the chamber 26 is such that this fluid under pressure may still have a substantial pressure while it is in the passage 15, and in this event the fluid under pressure could flow through the opening 41 into the tube 39 and through the bores 33 thereof to the enclosure 32 to move the diaphragm 28 to its closed position. In other words, because of the size of the passage 15 it sometimes happens that there is still in the fluid which is discharging from the inflatable assembly sufficient pressure to move the diaphragm 28 to its closed position and the fluid can no longer discharge from the chamber 26 in the manner desired, even though the ball valve member 36 is raised from the opening 41. In order to prevent this undesirable result there is provided a means 62 shown in detail in FIG. 6 for limiting the flow of fluid from the chamber or enclosure 32 to the outer atmosphere. In other words, the means 62. prevents fluid from flowing from the outer atmosphere into the enclosure 32, and as a result of the means 62 fluid can only reach the enclosure 32 from the interior of the chamber 26. The dished wall 31 fixedly carries at its exterior a tubular member 63 which is welded, for example, to the dished wall 31, and this tubular member 63 is coaxial with the tube 30. The tubular member 63 fixedly carries in its interior the means 62. This means 62 is in the form of an annular member 64 of rubber or the like, for example, and it is fixed in any desired way in the interior of the tube 63 adjacent to the plate 40 which extends across and is fixed to the tube 30. For example, the outer periphery of the member 64 may be glued to the inner surface of thetube 63 with the member 64 located in the position indicated in FIG. 4. As is apparent from FIG. 6, the Wall of the member 64 which extends across the annular periphery of the member 64 is formed with an arcuate slot 65 which extends almost along a complete circle so as to leave a flap 66- joined to the member 64- by the relatively small'neck portion 67. This flap -66 cooperates with the opening 41 of the plate 40 in the manner of a non-return valve. The flap 66 will not prevent fluid from flowing from the enclosure 32 out through the opening 41 and past the flap 66 to the outer atmosphere, and this fluid can easily move the flap 66 away from the opening 41. However, when there is any tendency of fluid to flow in the reverse direction the fluid itself will press the flap 65 against the opening 41 so as to close this opening, and thus it is impossible for fluid to how from the passage 15, for are ample, into the opening 4'1. Thus, with this construction it cannot happen that fluid which still has a considerable pressure in the passage reaches the enclosure 32. to move the diaphragm 28 to its position closing the opening 27.

It should be noted that the endless member 18 reliably prevents any of the particulate material in the storage bin from reaching the space 19' between the wall 14 and the wall 16, so that it is impossible for any of the particulate material within the storage bin to be swept out of the latter with air which is discharging through the passage 15. It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of inflatable assemblies differing from the types described above.

While the invention has been illustrated and described as embodied in deflatable assemblies for storage bins and the like, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential char acteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. For use in storage bins or the like, an inflatable assembly comprising, in combination, a rigid wall and a substantially coextensive stretchable wall fluid-tightly joined at its periphery to the periphery of said rigid wall and defining therewith a chamber whose interior volume increases during stretching of said stretchable wall while fluid under pressure is introduced into the space between said walls; valve means carried by said rigid wall for closing off the interior of said chamber from the outer atmosphere when said valve means is in a closed position and for placing the interior of said chamber in communication with the outer atmosphere when said valve means is in an open position; and valve-operating means connected to said stretchable wall and said valve means for automatically moving the latter to said open position thereof when said stretchable wall has been stretched beyond a given extent, said valve-operating means including a plurality of elon ated, endless, stretchable bands each operatively connected at one end to said valve means and at its opposite end to said stretchable wall.

2. For use in storage bins or the like, an inflatable assembly comprising, in combination, a rigid wall and a substantially coextensive stretchable wall fluid-tightly joined at its periphery to the periphery of said rigid wall and defining therewith a chamber whose interior volume increases during stretching of said stretchable Wal while fiuid under pressure is introduced into the space between said walls; valve means carried by said rigid wall for closing off the interior of said chamber from the outer atmosphere when said valve means is in a closed position and for placing the interior of said chamber in communication with the outer atmosphere when said valve means is in an open position; and valve-operating means connected to said stretchable wall and said valve means for automatically moving the latter to said open position thereof when said stretchable wall has been stretched beyond a given extent, said valve-operating means including a plurality of elongated, endless, stretchable bands each operatively connected at one end to said valve means and at its opposite end to said stretchable wall, and said valve-operating means including a support member fixed to said valve means and a plurality of rollers turnably carried by said support member, said endless bands respectively extending around and engaging said rollers so that said support member and rollers serve to operatively connect said endless bands to said valve means.

3. For use in storage bins or the like, an inflatable assembly comprising, in combination, a rigid wall and a substantially coextensive stretchable wall fluid-tightly joined at its periphery to the periphery of said rigid Wall and defining therewith a chamber whose interior volume increases during stretching of said stretchable Wall while fluid under pressure is introduced into the space between said walls; valve means carried by said rigid Wall for closing off the interior of said chamber from the outer atmosphere when said valve means is in a closed position and for placing the interior of said chamber in communication with the outer atmosphere when said valve means is in an open position; and valve-operating means connected to said stretchable wall and said valve means for automatically moving the latter to said open position thereof when said stretchable wall has been stretched beyond a given extent, said valve-operating means including a plurality of elongated, endless, stretchable bands each operatively connected at one end to said valve means and at its opposite end to said stretchable wall, said valveoperating means including a plurality of rollers respectively fixed to said stretchable wall at its inner surface and about which said bands are respectively guided.

4. For use in storage bins or the like, an inflatable assembly comprising, in combination, a rigid wall and a substantially coextensive stretchable Wall fluid-tightly joined at its periphery to the periphery of said rigid wall and defining therewith a chamber whose interior volume increases during stretching of said stretchable wall while fluid under pressure is introduced into the space between said walls; valve means carried by said rigid wall for closing off the interior of said chamber from the outer atmosphere when said valve means is in a closed position and for placing the interior of said chamber in communication with the outer atmosphere when said valve means is in an open position; and valve-operating means connected to said stretchable wall and said valve means for automatically moving the latter to said open position thereof when said stretchable wall has been stretched beyond a given extent, said valve-operating means including a plurality of elongated, endless, stretchable bands each operatively connected at one end to said valve means and at its opposite end to said stretchable wall, said valveoperating means including a plurality of rollers respectively fixed to said stretchable Wall at its inner surface and about which said bands are respectively guided, said stretchable wall having in its interior a plurality of projections, and a plurality of clamp members respectively turnably carrying said rollers and respectively clamping said projections for fastening said rollers to said projections of said stretchable wall.

5. For use in storage bins or the assembly comprising, in combination, a rigid Wall and a substantially coextensive stretchable wall fluid-tightly joined at its periphery to the periphery of said rigid wall and defining therewith a chamber whose interior volume increases during stretching of said stretchable wall while fluid under pressure is introduced into the space between said walls; valve means carried by said rigid wall for closing off the interior of said chamber from the outer atmosphere when said valve means is in a closed position and for placing the interior of said chamber in communication with the outer atmosphere when said valve means is in an open position; and valve-operating means connected to said stretchable wall and said valve means for automatically moving the latter to said open position thereof when said stretchable wall has been stretched like, an inflatable beyond a given extent, said valve-operating, means including a plurality of elongated, endless, stretchable bands each operatively connected at one end to said valve means and at its opposite end to said stretchable wall, said valveop erating means including a plurality of rollers respectively fixed to said stretchable wall at its inner surface and about which said bands are respectively guided, said stretchable Wall having in its interior a plurality of projections, and a plurality of clamp members respectively turnably carrying said rollers and respectively clamping said projections for fastening said rollers to said projections of said stretchable wall, said stretchable wall when said chamber is deflated being substantially unstretched and located adjacent to said rigid wall and said projections of said stretchable wall engaging said rigid wall to prevent the inner surface of said stretchable wall from coming into direct engagement with said rigid wall at least in the region of said projections whereby there is maintained between said walls a layer of air which cushions the falling'of any material onto said stretchable wall and which reduces the frictional rubbing of the inner surface of said stretchable wall on said rigid wall.

v6,. For use in storage bins or the like, an inflatable assembly comprising, in combination, a rigid wall and a substantially coextensive stretchable wall fluid-tightly joined at its periphery to the periphery of said rigid wall and defining therewith a chamber whose interior volume increases during stretching of said stretchable wall while fluid under pressure is introduced into the space between said walls; valve means carried by said rigid wall for closing off the interior of said chamber from the outer atmosphere when said valve means is in a closed position and for placing the interior of said chamber in communication with the outer atmosphere when said valve means is in an open position; and valve-operating means connected to said stretchable wall and said valve means for automatically moving the latter to said open position thereof when said stretchable wall has been stretched beyond a given extent, said valve-operating means including a plurality of elongated, endless, stretchable bands each operatively connected at one end to said valve means and at its opposite end to said stretchable wall, said endless bands respectively being uniformly distributed about said valve means and symmetrically arranged with respect to said stretchable wall.

7. For use in storage bins or the like, an inflatable assembly comprising, in combination, a rigid wall and a substantially coextensive stretchable wall fluid-tightly joined at its periphery to the periphery of said rigid wall and defining therewith a chamber whose interior volume increases during stretching of said stretchable wall while fluid under pressure is introduced into the space between said walls; valve means carried by said rigid wall for closing oil the interior of said chamber from the outer atmosphere when said valve means is in a closed position and for placing the interior of said chamber in communication with the outer atmosphere when said valve leans is in an open position; and valve-operating means connected to said stretchable wall and said valve means for automatically moving the latter to said open position thereof when said stretchable wall has been stretched beyond a given extent, said valve-operating means including a plurality of elongated, endless, stretchable bands each operatively connected at one end to said valve means and at its opposite end to said stretchable wall, said valveoperating means including a plurality of rollers connected with said valve means and about which said bands are respectively guided for being operatively connected to said valve means and said valve-operating rneans also including a plurality of rollers connected to said stretchable wall and about which said endless bands are also respectively guided.

Belgium Feb. 29, 1956 

1. FOR USE IN STORAGE BINS OR THE LIKE, AN INFLATABLE ASSEMBLY COMPRISING, IN COMBINATION, ARIGID WALL AND A SUBSTANTIALLY COEXTENSIVE STRETCHABLE WALL FLUID-TIGHTLY JOINED AT ITS PERIPHERY TO THE PERIPHERY OF SAID RIGID WALL AND DEFINING THEREWITH A CHAMBER WHOSE INTERIOR VOLUME INCREASES DURING STRETCHING OF SAID STRETCHABLE WALL WHILE FLUID UNDER PRESSURE IS INTRODUCED INTO THE SPACE BETWEEN SAID WALLS; VALVE MEANS CARRIED BY SAID RIGID WALL FOR CLOSING OFF THE INTERIOR OF SAID CHAMBER FROM THE OUTER ATMOSPHERE WHEN SAID VALVE MEANS IS IN A CLOSED POSITION AND FOR PLACING THE INTERIOR OF SAID CHAMBER IN COMMUNICATION WITH THE OUTER ATMOSPHERE WHEN SAID VALVE MEANS IS IN AN OPEN POSITION; AND VALVE-OPERATING MEANS CONNECTED TO SAID STRETCHABLE WALL AND SAID VALVE MEANS FOR AUTOMATICALLY MOVING THE LATTER TO SAID OPEN POSITION THEREOF WHEN SAID STRETCHABLE WALL HAS BEEN STRETCHED BEYOND A GIVEN EXTENT, SAID VALVE-OPERATING MEANS INCLUDING A PLURALITY OF ELONGATED, ENDLESS, STRETCHABLE BANDS EACH OPERATIVELY CONNECTED AT ONE END TO SAID VALVE MEANS AND AT ITS OPPOSITE END TO SAID STRETCHABLE WALL. 